1. Field of the Invention
The present invention relates to the structure of a branch connector, such as a branch pipe or branch metal fitting, which is for use with a hlgh-pressure branched fuel pipe and, more particularly, to the structure of a branch connector for use with a high-pressure branched fuel pipe whose inside pressure is in excess of 1000 kg f/cm.sup.2 and which acts as a fuel supply passage to a Diesel engine.
2. Description of the Prior Art
FIG. 10 is a side elevatlon partially in cross section of a conventional branch connector for use with a high-pressure branched fuel ppe, for showing the structurc of the connector. As an example, this branch connector is a branch pipe. The main pipe is indicated by reference numeral 11. A circulation passage 10 through which high-pressure fuel circulates is formed in the main pipe 11. A plurality of holes 13 (only one is shown in FIG. 10) extend perpendicularly to this circulation passage 10. The holes 13 are spaced from each other along the axis of the circulation passage 10.
A branch pipe 14 is fitted in each hole 13. The branch pipe 14 is brazed or welded to the drain pipe 11 at the junction w between them. The circulation passage 10 in the main pipe 11 is in communication with a fluid passage 12 formed inside the branch pipe 14.
Ultrahigh pressure exceeding 1000 kg f/ cm.sup.2 is repeatedly supplied to the above-described branch connector for use with the high-pressure branched fuel pipe. Moreover, vibration is transmitted to the connector from the Diesel engine. Therefore, the junction w or its vicinities affected by heat tend to crack, or the connector is broken down, permitting the fuel to splash or leak out. Also, the branch pipe 14 may be disconnected.